Although the term “developmental disorder” has become pretty well known, it is not yet fully understood. How should the family or the people around the person concerned relate to him/her? His/her family members or those who are around him/her suffer for a long period of time due to the “difficulties in social life,” which is a characteristic of developmental disorder. The author wrote this book with the desire to see the people with the developmental disorder live their lives a little easier and documented the growth of a father (the author) and his first son (the person concerned), as they overcame various challenges together.